mix of random data and a fixed pattern. The fixed pattern is either zeros,
or the pattern specified by \fBbuffer_pattern\fR. If the pattern option
is used, it might skew the compression ratio slightly. Note that this is per
-block size unit, for file/disk wide compression level that matches this
-setting, you'll also want to set \fBrefill_buffers\fR.
+block size unit, see \fBbuffer_compress_chunk\fR for setting a finer granularity
+of compressible regions.
.TP
.BI buffer_compress_chunk \fR=\fPint
See \fBbuffer_compress_percentage\fR. This setting allows fio to manage
will provide \fBbuffer_compress_percentage\fR of blocksize random data,
followed by the remaining zeroed. With this set to some chunk size smaller
than the block size, fio can alternate random and zeroed data throughout the
-I/O buffer.
+I/O buffer. This is particularly useful when bigger block sizes are used
+for a job. Defaults to 512.
.TP
.BI buffer_pattern \fR=\fPstr
If set, fio will fill the I/O buffers with this pattern or with the contents